1. Field of the Invention
The present invention relates to a method of driving a display device such as a ferroelectric liquid crystal. The invention also relates to a driving control apparatus for driving and controlling such a ferroelectric liquid crystal display apparatus.
2. Description of the Related Art
In recent years, rapid progress has been made in the development of ferroelectric liquid crystal devices which are to be used in place of conventional nematic liquid crystal devices. Briefly, a ferroelectric liquid crystal device employs a pair of substrates spaced by a distance which is small enough to enable control of the spiral arrangement of liquid crystal molecules in a chiral smectic C phase of a bulk state, e.g., in the form of a thin cell having a thickness of 1 to 2 .mu.m. The liquid crystal molecules are arranged between these substrates and, in addition, vertical molecule layers each composed of a plurality of liquid crystal molecules are arranged unidirectionally. Ferroelectric liquid crystal devices are generally superior both in memory characteristics and response speed and, hence, are expected to enable development of large-size display apparatuses having such superior characteristics.
Thus, it has been proposed to produce a display device having a large display area presented by ferroelectric display element with scanning and data electrodes arranged in a matrix form. Production of such a large-size ferroelectric liquid crystal display device, however, is encountered with the following problems. Namely, a drivable region tends to be extremely restricted or, in the worst case, completely extinguished due to change in the ambient temperature or local temperature difference in the cell, with the result that the display panel cannot display information. Expansion of the drivable region is therefore an important object in the development of ferroelectric liquid crystal display device. In addition, minimization of the time required for forming one picture frame is still an important object, from a view point of display speed.